8 COE 



2. Color brown or chocolate with numerous narrow, transverse white rings 



and five parallel, longitudinal white lines, of which one is in the dorso- 

 median line, and two on each lateral surface C. dinema, p. 15. 



3. Color brown with numerous narrow transverse rings and three parallel, lon- 



gitudinal white lines of which one is in the dorso-median line and one just 

 below each lateral margin C. capistrata, p. 16. 



Order MESONEMERTEA. 



A. Body musculature consists of a thin outer circular layer and a 

 strong inner longitudinal layer an inner circular layer is 

 usually wanting entirely, or, if present, is much reduced. Body 

 long and filiform, often coiled in a close spiral. Head sharply 

 pointed. Mouth placed very far behind the brain. Neph- 

 ridia not discovered Cephalothrix, p. 19. 



I. Slender, filiform, pale yellow, sometimes with reddish, grayish or greenish 

 tinge. No ocelli in adult C. linearis, p. 19. 



AA. Body musculature consists of a thin outer circular layer, a 

 diagonal layer, a longitudinal laj'er, and, in the esophagal re- 

 gion, an additional, enormously developed inner circular layer. 

 Head broader than neck. Nephridia well developed. 



Carinoma, p. 20. 



1. Body rather stout, flattened posteriorly. Mouth close behind brain. Milk- 

 white with grayish or brownish mottlings, and darker intestinal lobes. 



C. griffini, p. 20. 



Order METANEMERTEA. 



A. Body long and slender. Proboscis sheath usually less than half 

 the length of body. Proboscis small ; central stylet usually 

 small Emplectone?na, p. 23 . 



1. Stylets slender, curved. Dark green or pale green above, and whitish or 



very pale greenish below E. gracile, p. 23. 



2. Stylets straight and short, with swollen bases. Basis of central stylet 



swollen and rounded posteriorly. Dark brown above, flesh-color be- 

 neath... E. biirgeri, p. 25. 



AA. Body moderately elongated. Proboscis sheath about ^ to ^ the 

 length of body. Central stylet well developed. 



Paranemertes, p. 32. 



1. Two or 4 pouches of accessory stylets. Color purplish brown, dark-brown, 



or orange-brown above, on sides, and on lateral margins of ventral sur- 

 face; rest of ventral surface (often only the median third) white or 

 yellowish white P. peregrina, p. 33. 



2. Four pouches of accessory stylets. Opaque white P. pallida, p. 36. 



